Upcoming Changes to GB Maximum Residue Levels (MRLs): Emamectin and Thiabendazole

The Health and Safety Executive (HSE) has proposed a series of amendments to Great Britain's Maximum Residue Levels (MRLs) for two pesticide substances—emamectin and thiabendazole—in light of new safety concerns.

Emamectin: Proposed Reductions Due to Health Risks

Emamectin, which is not currently approved for use in Great Britain, has raised concerns due to potential risks to human health through dietary exposure. Based on updated assessments, HSE is recommending the following changes:

to the

Milk: MRL to be reduced from

 In addition, HSE proposes adopting Codex MRLs for several other commodities: Chinese cabbages & other leafy brassicas – 0.2 mg/kg Spinach – 0.05 mg/kg Tea – 0.1 mg/kg Edible offals – 0.1 mg/kg  Thiabendazole: Lowering MRLs for Bird Eggs Thiabendazole, currently approved for use in GB, has also been flagged for intake concerns—particularly with respect to birds' eggs. 

To mitigate potential health risks, HSE proposes: Reducing the MRL for thiabendazole in birds' eggs from 2 mg/kg to the CXL of 0.1 mg/kg Proposed date of adoption and publication: 2 September 2025

The draft reasoned opinion is available on HSE's website. To align with the UK's international trade commitments, the proposed changes have been notified to the World Trade Organization (WTO). Final updates and implementation timelines will be shared through the HSE's ebulletin service.